Mold



Semi. 30, 1924. I R,509,9?8

- E. PASCUCC! MOLD Filed April 13. 1921 3 Sheets-Sheet 1 Fin, 1. H

v INVENTOR Emilia .Pasnuum ATI'ORNEY Sept. 30. 1924. 7 1,509,978

E. PASCUCCI MOLD' Filed April 13. 1923 Sheets-Sheet 2 & INVEB: Emilia Pa TOR suucni ATTORNEY Sept. 30, 1924. 1,509,978

E.PASCUCCI MOLD Filed April l3.-l921 '3 SheetsSheet INVENTOR Emilio Pas ucci ATTORNEY Patented Sept. 30, 1924.

UNITED STATES PATENT OFFICE.

H410 PASCUGCI, OI COBN ING, NEW YORK, ASSIGNOR T0 CORNING GLASS WORKS,

' OF GOBNING, NEW YORK, A CORPORATION OF NEW YORK.

MOLD.

Application filed April 13, 1921. Serial 110. 461,066.

To all whom it my concern:

Be it known that I, EMILIO PASCUCCI, a citizen of the United States of America, and a resident of Coming, New York, have invented certain new and useful Improvements in Molds, of which the following is a specification.

This invention relates to the manufacture of spark lugs having cores of pressed glass, and one o ject is to provide a mold for forming the cores wherein the parts constituting the molding cavity cooperate in an improved manner, and wherein means of improved construction are employed for holding the metal parts of. the spark plug during the forming operation.

A further feature of this invention is in the construction of the mold with insulated sections for the urpose of enabling an electric current to e passed through the electrode, so as to heat it toinsure a joint between it and the glass.

The invention consists in the novel features of construction and in the combination of parts hereinafter fully described and claimed.

In the accompanying drawings Figure I, is a vertical section through a mold for use in the manufacture of spark plug cores, the parts being shown assembled and ready for the introduction of a charge of molten glass, the mold plunger being omitted;

Fi II, is a vertical section taken on the line TI-II of Figure I, showing the glass pressed in the'mold cavity;

Fig. III, is a horizontal section throu h the upper portion of the mold taken on t e line III-III of Figure I;

Fi IV, is a horizontal section taken on the hue IV-JV of Figure I, and

Fig. V, is an inverted view of the upper portion of the mold, the parts thereofbeing separated slightly.

The spark plug core which is adapted to be made in the mold forming the subject matter of this invention comprises a central electrode 1 having an upper portion 2 formed of some low expansion metal of relatively small diameter which can be sealed in the glass of which the core is made, and a lower portion 3 larger in diameter and of some metal which stands up under the conditlons to which the spark points are subected, the two parts of the electrode being welded, or otherwise firmly seamed together. Fastened to the upper extremity of the electrode portion 2 is a wiringterminal in the form of a cap 4:. The core is molded into form around the central electrode 1 and w1thin the cap 4, and also withina band 5 which surrounds its central portion, the interior of the band 5 having rounded annular corrugations 6 therein to anchor the glass'within the band. The external contour of the core may closely approach, or be identical with standard practice.

The mold comprises a base portion 7, and a top portion 8 that is made of separable, and preferably, of hinged halves. The base 7 has in its upper face a recess 9 forming the lower part of the mold cavity. The upper end of this cavity has a diameter suflicient to receive the lower half of the band 5, a shoulder being formed in the recess 9, immediately below such enlarged diameter, to form a seat for the band. In practice, a block 10 may be inserted in the base 7, and the center of this block is'recessed with a contour to form the tip portion of the core.

The hinged halves forming the 'top portion 8 of the mold are similarly formed and they each have a central recess 12 registering, when the mold parts are assembled, with the recess 9 in the base. The recess 12 is large enough at its bottom end to take in the upper half of the band 5, the upper portion thereof being of the general contour desired for the core above the band.

In order to hold the top portion of the mold in place on the base, the upper surface I of the base surrounding the recess 9 therein is formed into a boss 13, havin undercut walls 14, and the top portion 8 0% the mold has a similarly shaped recess formed in its bottom, and when its two halves are assembled together on the base, and locked againstseparation, it will be firmly anchored on the base.

The halves of the top portion of the mold are shown as provided with pieces in the form of rectangular blocks 15 that are inserted therein and held in place by means of screws (see Fig. V), a layer of insulating material 16, such as mica, being interposed between the contacting surfaces of the blocks and halves of the top section. Inthese blocks is preferably formed the central recess 12 for receiving the upper half of the band 5 and also the lower part of the portion of the cavity! forming the core above the band 5. The cavity is extended above the band 5 and its upper iportion, which is within the top portion 0 to receive and support the cap 4 on the upper end of the electrode.

A font cavity 17 is formed in the upper part of the top section, and communicates by sprue passages 18 with the core cavity, entering the same below the space occupied by the cap. In the drawings, these passages are shown as formed in part in the blocks 15.

The construction of the top portion of the mold is such, that when the hinged sections thereof are assembled on the base, with the metal parts of the spark plug core positioned in the mold cavity, the part of the mold in which is placed the cap 4 will be separated by the insulation 16 from the part thereof in which the band 5 is placed, the band 5 being supported by the recess 9 in the base portion 7 and the recess 12 formed in blocks 15 of the top mold section.

The base portion 7 of the mold, below the recess 9 therein, is bored. axially of the mold cavity, as at 19, and also bored radially thereto. In the latter bore is contained a clamping screw 20.

In forming the core, the electrode, with the cap 4 fastened thereon, has its lower end inserted in the vertical bore 19 of the lower section, a plate 21 on the bottom of the section serving to pro erly position it, and is clamped in place by the screw 20. The band 5 is slipped over the upper extremity of the electrode and inserted in the enlarged upper end of the recess 9 in the lower section 7. The halves of the upper section are then closed around the boss 13 on the lower section.

The electrode now has its lower end firmly held in the lower section, and its upper end in the upper section. If the upper and lower mold sections are now included as a part of an electric circuit fed from a proper source of energy by means of wires 22 and 23 that are respectively attached to the upper and lower sections, current will flow through the electrode, the in-- sulating layer 16 restraining it'to this path. The current should be of sufficient volume to heat to incandescence the electrode, whereby gases occulded therein will be driven off. After this action has taken place, and while the electrode is still hot, glass which has been placed in the font the mold, is adapted cavity 17 in any proper way, is forced by the action of a plunger 24 to flow through the sprue passages into the mold cavity formed by the recesses in the top and bot" tom sections. In doing this, it flows up into the cap 4, and around the electrode, and within the band 5, to which it unites itself by a joint in the nature of a weld. As the occulded gases have been drawn out of the electrode, it will be found that the joint between the electrode and the glass is good, and free of air bubbles which would otherwise be present and tend to leakage.

The glass having set, the mold is opened and the glass with its surrounding band and enclosed electrode taken out. The sprues and excess glass in the font cavity are then removed by breaking them off and grinding.

Having thus described my invention what I claim as new is 1. A mold for forming glass articles on metal, comprising a plurality of parts, each adapted to hold an end of the metal on which the glass is to be welded, the said mold parts being insulated from each other but forming a continuous mold cavity.

2. A mold for glass articles, comprising a plurality of parts forming a molding cavity, two of said parts having means thereon to clamp an electrode, around which glass is to be welded, and means for insulating the two said parts from each other.

3., A glass spark plug core mold having a molding cavity provided with a recess for retaining in position the terminal cap on the upper end of the electrode, means for clamping the lower end of the electrode in the mold body, and means for heating the electrode when it is clamped in position.

4. A mold having a molding cavity therein and having means whereby a metal part may be positioned in the cavity with its ends in electrical contact with the mold, means for electrically insulating that por- .tion of the mold having electrical contact with one end of the piece of metal from that portion of mold having electrical contact with the other end of the piece of metal, whereby an electrical current may be passed throu h the mold and metal part, for driving 0% occulated gases from the metal, and means for feeding molten glass into the mold cavity.

5. A mold having a molded cavity and having molding parts electrically insulated from each other, and having means whereby a metal part may be positioned in the cavity with its opposite ends in electrical contact with the said electrically insulated molding parts, whereby an electrical current may be passed through the insulated molding parts and through the metal while the latter is in position in the molding cavity.

6. A mold of the class described comprising a base portion and an upper portion adapted to be assembled on the base, said upper portionconsisting of hinged halves, means formed on the base for anchoring the upper portion, a cavity formed in part in the base and in part in the up er portion, an electrode centrally positioneg axially in said cavity and retained by the upper and base portions of the mold, and means for insulating the upper portion of the mold 10 from the base portion thereof. f

In testimony whereof, I hereunto sign my name.

EMILIO PASGUCCI. 

